In U.S. Pat. No. 3,009,309 fluid jets are disclosed for treating textile yarns. These jets include a central chamber through which the yarn may pass and a plurality of fluid inlets arranged along the chamber to allow gaseous treating fluid to pass circumferentially around the chamber. This treating fluid produces a yarn which is rounder and more compact in appearance than the flat yarns typically produced in a glass fiber yarn forming operation. The yarn produced in this manner is "false twisted", i.e., appears to be twisted continuously in one direction. Yarn, as referred to in this specification, includes twisted yarns, untwisted strands, rovings of strands and the like.
In U.S. Pat. Nos. 2,990,671 and 3,079,745, fluid jets are disclosed which includes a pair of opposing treating chambers. These jets are employed to produce a plurality of alternate direction false twists in the yarn by maintaining the yarn in the opposing chambers for a significant length of time to produce a plurality of twists in the yarn in each direction before moving the yarn into the other chamber.
While the yarns produced in these manners have utility in fabric production, it is often desirable to produce textile fabrics having novelty patterns, such as slubs and other texturized effects. It is also desirable to produce textile yarns which are not twisted or false twisted, but which are consolidated and rounded to such a degree that the yarns will process satisfactorily in weaving and other textile operations.
In co-pending U.S. Application Ser. No. 749,198 now U.S. Pat. No. 4,096,685 granted June 27, 1978, which is incorporated herein by reference, numerous nozzled apparatuses are disclosed for producing slubbed yarns. It is theorized that the slubs are provided by a "double-vortex" effect. Thus, a pair of counterdirectional gaseous fluid streams are created within a treatment zone by the nozzles, with the yarn alternately passing within the gaseous fluid streams and with the counterdirectional gaseous fluid streams twisting and untwisting the yarn in opposite directions. At the null points, i.e., the points of direction reversals in the twist, slubs are produced in the yarn.
While the texturizing apparatuses of U.S. Ser. No. 749,198 have provided slub yarns of good quality, it is desirable to more precisely control the production of these yarns and to highlight the "double-vortex" effect which is believed to produce these slubs. At the same time, it is desirable to produce numerous and varied textile texturizing effects on a textile yarn under various fluid pressures and with different levels of tension on the yarn. It is also desirable to produce untwisted and untexturized yarns which will process satisfactorily in textile operations. Further, it is desirable to produce such yarns from a fluid jet which requires no nozzle which must be carefully adjusted to produce the desired effects.